Can someone be "too old" or "too late" for physics? I am a first year physics student, but I am 20 years old (pretty old for my country, average starting age is 18), because I started after leaving med school, which I find extremely jailed in "memorization walls", with no place for analytical problem solving, something that I have loved all my life. I started to love physics because I was introduced to neuroscience, which lead me to information theory, probability analisis, mathematics and physics. I decided to study physics not only because I practically become obsessed with any problem I encourage, but also because I find physics to be the only "real" foundation of the understanting of nature, thanks to its mathematical basis. Well, now the problem is that I constantly see that most physicists that discover great things all started very very young, which is not my case. So, besides I am really good at math (the first of my class), I am periodically dissapointed about the fact that I am maybe too old to make a difference, and this sometimes brings me back to think if I made the right decision when I left med school. The thread here is about sharing information about cases of physicists that did great discoveries without being extremely precocious or "geniuses" since they were kids. Also your opinion about this kind of situation would be of real help. What do you think?